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Clinical Psychologist

John W. Dettwyler

Sees patients in Lewes, DE · Delaware

Summary

John W. Dettwyler is a clinical psychologist at 119 W 3rd St, Lewes, DE 19958. Phone: (302) 234-8982. Accepts Medicare assignment. In 2024, John W. Dettwyler had 210 Original Medicare patients and 299 services. NPI 1982776324. Source: CMS National Downloadable File, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Clinical psychologist
  • Address: 119 W 3rd St, Lewes, DE 19958 · Directions
  • Phone: (302) 234‑8982
  • Medicare: Accepts Medicare assignment
  • School: Temple University School Of Medicine · graduated 1987
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about John W. Dettwyler, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does John W. Dettwyler accept Medicare assignment?
Yes. Medicare's clinician data says John W. Dettwyler accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does John W. Dettwyler see?
In 2024, CMS data shows 210 Original Medicare patients and 299 services for John W. Dettwyler. This counts Original Medicare only and measures volume, not quality.
What is John W. Dettwyler's NPI number?
1982776324. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for John W. Dettwyler, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients210
Services billed to Medicare299
Different services or procedures3
Participating Medicare providerYes
Average age of these patients73

Most frequent services

  1. Psychiatric diagnostic evaluation (90791)202 services
  2. Psychotherapy, 1 hour (90837)83 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Arthritis75%
  • Diabetes46%
  • Anxiety39%
  • Depression34%

Practice locations

Addresses where John W. Dettwyler is enrolled with Medicare (CMS data updated October 2, 2026).

Specialties

Find other clinicians: Clinical Psychologist, Delaware →

Other clinical psychologists in Lewes

Clinicians with the same Medicare primary specialty in Lewes, DE — not a recommendation.

All clinical psychologists in Lewes →

Clinician information

SchoolTemple University School Of Medicine
Graduation year1987
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1982776324
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians